1. Field of the Invention
The present invention relates to a socket for electrical parts that is used for performance tests on electrical parts such as IC packages.
2. Related Art
An example of sockets for electrical parts of a known type is described in Japanese Unexamined Utility Model Application Publication No. 7-42063A. According to the description, a semiconductor device is placed on a semiconductor-device-holding plate, and handling member is depressed. In accordance with this downward movement of the handling member, the semiconductor-device-holding plate is shifted outside of the side wall of the socket and thus detached from the semiconductor device. On the other hand, in accordance with the downward movement of the handling member, a pressing member depresses the peripheral portion of the semiconductor device and thus the semiconductor device is fitted on the bottom wall of the socket.
According to such a socket for electrical part, in accordance with the downward movement of the handling member, the pressing member is rotationally moved through a rack and a pinion to press the semiconductor device and thus the stroke of the handling member is long. Moreover, the pressing member is rotationally moved at a predetermined speed. Therefore, as the rotation speed of the rack and pinion increases, the test time can be shortened but the chance of giving a shock to the electrical part might increase at the time of pressing. On the other hand, as the rotation speed of the rack and pinion decreases, the chance of giving a shock to the electrical part is diminished but the test time is prolonged.
Due to the limited rotational movement of the rack and pinion, the pressing portion of the pressing member moves in an arc. Therefore, the pressing portion depresses the electrical part obliquely, not perpendicularly, and may thus scratch the upper surface of the electrical part.